1. Field of the Invention
This invention relates to a poly-V grooved pulley, and more particularly to a poly-V grooved pulley with ribs as well as a method of making the same.
2. Description of the Prior Art
There has been previously employed a poly-V grooved pulley of sheet metal for use with a poly-V belt in a driving system of a vehicle. In a conventional poly-V grooved pulley disclosed in U.S. Pat. No. 3,977,264, for example, a cylindrical flange wall on which a plurality of V-grooves are formed is terminated in an outturned flange so as to strengthen the flange wall. However, such a pulley is comparatively or relatively heavy in weight with the result that torque may not be transmitted efficiently.